Appendix B
Basics of Thermodynamics
Thermodynamics is a branch of physical-chemistry and physics that deals with
temperature (T), Heat (Q), Energy (E), or Work (W). Thermodynamics is based on
three classic principles or laws. The principles or laws have been extended to five,
with the introduction of the Zero law and Fourth law. Three properties are
commonly used in thermodynamics to express the behavior of a reactive system,
namely Enthalpy (H) that represents the heat released or up-taken in a process,
Entropy (S) that is related to the amount of heat that cannot be transformed into
useful work, and Free Energy (G) or Gibbs Energy that gives the useful work made
by the system.
The fundamental principles of thermodynamics are categorized below.
The Zero Law
This law states the condition of equilibrium of a system with respect to the
environment.
It states:
If two systems are in thermal equilibrium with a third system, then the three systems are in
thermal equilibrium with each other.
States of equilibrium are characterized by an equation of state, which relates the
experimentally accessible parameters, in general: Temperature (T, K), Volume (V,
L), Pressure (P, MPa). (The first letter in parentheses is the symbol of the property,
the second the unit of measure in the International System of Units.) In a reaction A
! B, the equilibrium reaction represents the condition in which the concentrations
of the species do not change macroscopically because the rate of the forward
process A > B and that of the back process B > A are equal.
© Springer Nature Switzerland AG 2021
M. Aresta and A. Dibenedetto, The Carbon Dioxide Revolution,
https://doi.org/10.1007/978-3-030-59061-1
233
Basics of Thermodynamics
Thermodynamics is a branch of physical-chemistry and physics that deals with
temperature (T), Heat (Q), Energy (E), or Work (W). Thermodynamics is based on
three classic principles or laws. The principles or laws have been extended to five,
with the introduction of the Zero law and Fourth law. Three properties are
commonly used in thermodynamics to express the behavior of a reactive system,
namely Enthalpy (H) that represents the heat released or up-taken in a process,
Entropy (S) that is related to the amount of heat that cannot be transformed into
useful work, and Free Energy (G) or Gibbs Energy that gives the useful work made
by the system.
The fundamental principles of thermodynamics are categorized below.
The Zero Law
This law states the condition of equilibrium of a system with respect to the
environment.
It states:
If two systems are in thermal equilibrium with a third system, then the three systems are in
thermal equilibrium with each other.
States of equilibrium are characterized by an equation of state, which relates the
experimentally accessible parameters, in general: Temperature (T, K), Volume (V,
L), Pressure (P, MPa). (The first letter in parentheses is the symbol of the property,
the second the unit of measure in the International System of Units.) In a reaction A
! B, the equilibrium reaction represents the condition in which the concentrations
of the species do not change macroscopically because the rate of the forward
process A > B and that of the back process B > A are equal.
© Springer Nature Switzerland AG 2021
M. Aresta and A. Dibenedetto, The Carbon Dioxide Revolution,
https://doi.org/10.1007/978-3-030-59061-1
233